PDF Publication Title:
Text from PDF Page: 131
4.3 Vacuum Cycle Example 4.3.1 Introduction This is an example of a cycle with a lower pressure that is below atmospheric. This is different from the previous example, as work is required to remove the gas from the adsorbent bed when the pressure is below Po. This work shows up on the left side of the Grassman diagrams, and is added to the work required to power the cycle. For comparison with the previous cases, the pressure ratio is again fixed at 15.6, but the lower pressure is set at 0.5 arm. 4.3.2 Vacuum Four-Step Cycle The system analyzed in this section is the same as that in Figure 4.4. However, as the lower pressure is reduced, the number of moles and energy flowing through the system are different. As both the upper and lower pressure limits are halved, and the pressure ratio remains constant, the molar values in Table 4.4 are exactly halved (this includes the productivity, which has units of mol/m3 ). The mole fractions remain the same as before, along with the recoveries. The Grassman diagram is shown in Figure 4.12. In comparing this with the Four-Step cycle depicted in the Grassman diagram of Figure 4.5, we see that although there are extra components of work input, the total work input per mole is less for the vacuum Four-Step cycle (82,549 J / m o l O2 vs. 106,207 J/mol O2 in Figure 4.5). Furthermore, once the energy recovered by expanding the product is subtracted, the net work for the separation is only 77,371 J/mol 02 . The reversibleworkofseparation(i|/p+V|/E =4149J/molO2)remainsthesame,sothesecond law efficiency is higher for the vacuum case than for the case with PL = 1 arm (5.36% vs. 4.18%). 115PDF Image | Energy Efficiency of Gas Separation Pressure Swing Adsorption
PDF Search Title:
Energy Efficiency of Gas Separation Pressure Swing AdsorptionOriginal File Name Searched:
ubc_1997-0009.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)